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Many companies are already using VoIP while incorporating video capabilities into their portfolio of services. One question that I am often asked is, “How can we ensure that the voice and video quality is good and consistent when using VoIP?”

Every second of every day, data is being sent and received. Billions of data packets are processed by your company’s network every day. In fact, you received dozens of packets just to read this article, but the vast majority of us have no idea how this works. People have no clue as to what goes on behind the scenes to ensure data actually gets to the right device.

Precision Time Protocol (PTP) is a protocol designed to go beyond what Network Time Protocol (NTP) can offer relative to accuracy. PTP is IEEE standard 1588 that can give local computing systems accuracy within the sub-microsecond range (such as microsecond, nanosecond or picoseconds) whereas NTP is within milliseconds or longer. PTP standard was first released in 2002 and known as 1588-2002. In 2008, the IEEE released a revised standard for PTP, known as 1588-2008, that improved the accuracy and precision of the protocol. It is also known as PTPv2 and is not backward compatible with the older version. PTP was developed for packet based network for control and measurement systems.

Configuring a wireless lab for study and testing capabilities is a bit more involved than you might think at first glance. Most of the requirements take place on the management devices, but the underlying switch infrastructure requires some preparations as well. The tasks involved are as follows:

The purpose of Interior Routing Protocols (IGP), and routing protocols more generally, is to advertise the existence of destination networks. All protocols then have some method of picking what they would consider to be the best path and maintain the information. By...

Previously, I talked about the logical and physical steps to building a basic certification lab, concentrating mostly on the CCENT/CCNA Routing and Switching level. Once you have that set of certifications under your belt, there are several options for specialization. Each of these advanced technology tracks serve as methods of enhancing your professional skill set as follows:

One size does not always fit all. At times there’s a need to run more than one routing protocol and have more than one routing domain: multivendor shops, migration from one protocol to another, scalability issues of a single protocol, political or personal preference, production versus test networks, mergers, and acquisitions.

Border Gateway Protocol (BGP) is a fascinating protocol because there are a lot of things that can be done with BGP. However, there has always been an issue with BGP, which is convergence (the time the network or protocol takes to accept change). BGP was designed for scale, not speed, so it’s something that we’ve had to tolerate from its inception.

License provisioning has always been a bit of a challenge in the CUCM environment. Prior to CUCM v9.0, licensing was managed on a per-cluster basis with each cluster requiring its own license files that were tied to the media access control (MAC) address of the cluster’s publisher. This approach to license management was limiting in the fact that one cluster might have unused licenses while another cluster may be at its limit and sharing between clusters was not possible.

With Multiprotocol Label Switching (MPLS) as popular as it is in the provider space and private MPLS clouds for larger enterprise, we needed some tools to help troubleshoot and maintain these networks. With the providers in mind, the normal ping or traceroute may not be enough.

Rodger Foster, our senior Cisco instructor, reviews how multiple gateways are used to provide redundancy in the network.

One of the most significant new features in Microsoft Windows Server 2012 is the Hyper-V Replica (HVR) capability. Whether you are considering this for your own organization or just prepping for your Windows Server 2012 MCSA, this white paper presents the essentials of deploying this disaster recovery feature.

The official Cisco CCNP Security FIREWALL training course (as well as other documentation) recommends enabling the inspection of the Internet Control Message Protocol (ICMP), even though it’s disabled by default. The image below displays the recommended practice as configured in ASDM, but the curious student might wonder what the unchecked “ICMP Error” box is. That’s what I’ll focus on in this post.

Cisco provides a wide array of connectivity and isolation tools within the datacenter. This white paper addresses Virtual Routing and Forwarding (VRF), which is a Layer 3 isolation mechanism for routing protocols.

When the hostname.domainname associated with my Small Office Home Office (SOHO) failed to update after a power outage, and a new DHCP-assigned external address was assigned to my router, I was reminded of the need for Dynamic DNS. This article will explore the implem...

The first big push toward implementation of IPv6 was mobile devices. Now, one of the driving forces is the Internet of Things. As the name implies, this means everything, including machine to machine communication (M2M).

Cisco Internetwork Operating System (IOS) has been around since a little after the inception of Cisco Systems as a company. In 1984, Len and Sandy Bosack from Stanford University founded Cisco Systems with a small commercial gateway server. The first Cisco router that I touched was an Advanced Gateway Server (AGS), which was the first marketed product of the company. After this came the Mid-Range Gateway Server (MGS), the Compact Gateway Server (CGS) and later the Integrated Gateway Server (IGS) and AGS+. The first version of IOS that I touched was 8.2(7). The operating system was based on a Unix-based system and was designed as a monolithic operating system, meaning that processes are stacked and interrelated.

Routers and switches make up the bulk of the network infrastructure and are vulnerable to attack. In a previous article, I talked about some of the different ways of hardening your network devices. In this blog, I’d like to specifically examine the routing protocols used on the major Cisco network operating systems.

An quick fundamental overview of layer two devices.   To learn more about this and similar topics, enroll in our exclusive Understanding Networking Fundamentals course.    

Global Knowledge Practice Leader, Craig Brown, explains what students will learn in our "Monitoring and Troubleshooting the Performance of a Windows Server Environment" workshop.

According to the Global Knowledge IT Skills and Salary Report, women make up 16% of the tech workforce, and an even smaller percentage (8%) are at the senior or executive level. Here’s an overview of the most popular and most pursued certifications by women in tech.

While cybersecurity remains the most popular certification category in our IT Skills and Salary Report, foundational-level certifications highlight our list of the most popular IT certifications of 2020. 

While there are differences between the IP Multicast configuration in the IOS and the Nexus OS, the Protocol Independent Multicast (PIM) protocol remains fundamentally the same. If you feel comfortable configuring Multicast in the IOS, you should be able to acclimate fairly easily to the changes in the Nexus OS.

Multicast Sparse Mode and its derivatives are supported in the Nexus OS. This white paper explains how it has been implemented in the Nexus platform to provide optimum performance in both virtual PortChannel and FabricPath environments.

ASA and PIX software version 7.0 introduced the configuration command nat-control which didn’t exist in previous versions of code. Although training course material for both the SNAF (Securing Networks with ASA Fundamentals) and SNAA (Securing Networks with ASA Advan...

Find out which OSI layer is concerned with reliable end-to-end delivery of data - and more. Get answers to your OSI reference model and network layer questions here.

Find out what changes have been made and how you now have multiple paths to success with the help of Cisco Certification 2020! The new set of certification exams launched on 24th February. It provides a common language for software developers and networkers to bring the two together. The certification programme will also open-up a brand new horizon of job roles and skill sets that are already starting to emerge. Announced at last year’s Cisco Live event in San Diego, the new DevNet certifications aim to help professionals combine infrastructure expertise with programming to take advantage of the possibilities of intent-based networking. Changes to the Cisco certification programme also include new training and certifications in five key technology tracks. In the traditional Cisco network programme, the certifications range from the associate level to the expert level. The new certification involves a DevNet Associate, a DevNet Professional and soon there will also be a DevNet Expert certification. In this one hour webinar, John Berry discusses what’s new in Cisco Certification, what the professional of the future should look like and how to prepare technology professionals for new roles as a network automation developer.

Looking ahead at new and emerging certifications provides insight into the areas deemed valuable in the IT industry. If you are an early adopter or in a position where you need to show that you have the bleeding-edge expertise of a technology, this list of recent and upcoming certifications is for you. 

As cybersecurity threats continue to be a top concern facing organizations today, the Information Technology (IT) Governance team must stay abreast in assuring that the organization is protected. The IT Governance team must continually evaluate the risks to the organization and put in place Processes, Procedures and Technologies to protect the assets of the organization.  

Now that we are moving towards IPv6, the logical move would be to also run OSPF for that protocol suite, which makes sense and reduces the learning curve for implementation and support. But, that would mean that you have to run two OSPF processes — one for IPv4 unicast and one for IPv6 unicast. That means two sets of policies have to be applied, including security for OSPF itself. Running OSPFv3 for both IPv4 and IPv6 reduces the number routing protocols and the configuration that goes with that. It makes it easier to implement policy in a consistent way for both protocol suites.

A video covering our Cisco Unified Communications courses - ACUCW1 & ACUCW2 - by Global Knowledge Course Director and Lab Topology Architect Joey DeWiele, a specialist in Unified Communications.

Understand the Cisco Collaboration technology and certification training portfolio. This overview will cover the courses needed to prepare for the CCNA Collaboration and CCNP Collaboration certifications. You will also learn about recommended skills-focused courses covering basic and advanced Unified Communications Manager administration.

Understand the Cisco Security technology and certification training portfolio. This overview will cover the courses needed to prepare for the CCNA Security and CCNP Security certifications. You will also learn about recommended skills-focused courses covering SourceFire technologies, the ASA security solution, and the ISE access control and authentication platform.

The Global Site Selector (GSS) leverages the Domain Name System (DNS) to provide clients with reliable and efficient content services. Domain to IP address mapping is performed with consideration for availability, location, and load of content servers. Using the GSS in combination with Cisco’s Content Services Switch (CSS), Cisco’s Catalyst 6000 Content Switching Module (CSM), or Cisco’s Application Control Engine (ACE) allows users to create Global Server Load Balancing (GSLB) networks.

Policy-based routing (PBR) provides network administrators with agility and flexibility to better manage traffic. With carefully architected policies, you can optimize how segments of your network process data, as well as how bandwidth is managed for business-critical applications.

What is PBR? Policy-Based Routin (PBR) is the process of using a route map to match on something more than the destination and then defining the path out of the router based on those conditions. PBR could match on destination only, but typically we would match on more. PBR is considered to be an exception to the RIB and is looked at before examining the RIB.

Global Knowledge Course Director and Lab Topology Architect Joey DeWiele, a specialist in Unified Communications, explains presence.

In this hour-long webinar, Global Knowledge instructor John Barnes will guide you through implementing Cisco private VLANs. He will review VLANs and 802.1q, and he will discuss private VLAN fundamentals and operation, covering primary VLANs and secondary VLANs. He will cover VLAN mapping and discuss using private VLANs between multiple switches. He will also provide a use case example.

Learn how to calculate QOS Bandwidth Percent vs Bandwidth Remaining Percent using a Cisco-defined formula. Read on for answers and examples from the experts at Global Knowledge!

In the previous discussion on QoS, the uses of Per-Hop Behaviors DiffServ to mark packets were identified and discussed in detail. Today’s post will identify the mechanisms to implement QoS. The five main categories of tools used to implement QoS are as follows. Cl...